2021-04-07 21:06:06

by Vineeth Pillai

[permalink] [raw]
Subject: [PATCH 5/7] KVM: SVM: hyper-v: Remote TLB flush for SVM

Enable remote TLB flush for SVM.

Signed-off-by: Vineeth Pillai <[email protected]>
---
arch/x86/kvm/svm/svm.c | 35 +++++++++++++++++++++++++++++++++++
1 file changed, 35 insertions(+)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index baee91c1e936..6287cab61f15 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -36,6 +36,7 @@
#include <asm/spec-ctrl.h>
#include <asm/cpu_device_id.h>
#include <asm/traps.h>
+#include <asm/mshyperv.h>

#include <asm/virtext.h>
#include "trace.h"
@@ -43,6 +44,8 @@
#include "svm.h"
#include "svm_ops.h"

+#include "hyperv.h"
+
#define __ex(x) __kvm_handle_fault_on_reboot(x)

MODULE_AUTHOR("Qumranet");
@@ -928,6 +931,8 @@ static __init void svm_set_cpu_caps(void)
kvm_cpu_cap_set(X86_FEATURE_VIRT_SSBD);
}

+static struct kvm_x86_ops svm_x86_ops;
+
static __init int svm_hardware_setup(void)
{
int cpu;
@@ -997,6 +1002,16 @@ static __init int svm_hardware_setup(void)
kvm_configure_mmu(npt_enabled, get_max_npt_level(), PG_LEVEL_1G);
pr_info("kvm: Nested Paging %sabled\n", npt_enabled ? "en" : "dis");

+#if IS_ENABLED(CONFIG_HYPERV)
+ if (ms_hyperv.nested_features & HV_X64_NESTED_ENLIGHTENED_TLB
+ && npt_enabled) {
+ pr_info("kvm: Hyper-V enlightened NPT TLB flush enabled\n");
+ svm_x86_ops.tlb_remote_flush = kvm_hv_remote_flush_tlb;
+ svm_x86_ops.tlb_remote_flush_with_range =
+ kvm_hv_remote_flush_tlb_with_range;
+ }
+#endif
+
if (nrips) {
if (!boot_cpu_has(X86_FEATURE_NRIPS))
nrips = false;
@@ -1112,6 +1127,21 @@ static void svm_check_invpcid(struct vcpu_svm *svm)
}
}

+#if IS_ENABLED(CONFIG_HYPERV)
+static void hv_init_vmcb(struct vmcb *vmcb)
+{
+ struct hv_enlightenments *hve = &vmcb->hv_enlightenments;
+
+ if (npt_enabled &&
+ ms_hyperv.nested_features & HV_X64_NESTED_ENLIGHTENED_TLB)
+ hve->hv_enlightenments_control.enlightened_npt_tlb = 1;
+}
+#else
+static inline void hv_init_vmcb(struct vmcb *vmcb)
+{
+}
+#endif
+
static void init_vmcb(struct vcpu_svm *svm)
{
struct vmcb_control_area *control = &svm->vmcb->control;
@@ -1274,6 +1304,8 @@ static void init_vmcb(struct vcpu_svm *svm)
}
}

+ hv_init_vmcb(svm->vmcb);
+
vmcb_mark_all_dirty(svm->vmcb);

enable_gif(svm);
@@ -3967,6 +3999,9 @@ static void svm_load_mmu_pgd(struct kvm_vcpu *vcpu, unsigned long root,
svm->vmcb->control.nested_cr3 = cr3;
vmcb_mark_dirty(svm->vmcb, VMCB_NPT);

+ if (kvm_x86_ops.tlb_remote_flush)
+ kvm_update_arch_tdp_pointer(vcpu->kvm, vcpu, cr3);
+
/* Loading L2's CR3 is handled by enter_svm_guest_mode. */
if (!test_bit(VCPU_EXREG_CR3, (ulong *)&vcpu->arch.regs_avail))
return;
--
2.25.1


2021-04-08 11:21:20

by Vitaly Kuznetsov

[permalink] [raw]
Subject: Re: [PATCH 5/7] KVM: SVM: hyper-v: Remote TLB flush for SVM

Vineeth Pillai <[email protected]> writes:

> Enable remote TLB flush for SVM.
>
> Signed-off-by: Vineeth Pillai <[email protected]>
> ---
> arch/x86/kvm/svm/svm.c | 35 +++++++++++++++++++++++++++++++++++
> 1 file changed, 35 insertions(+)
>
> diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
> index baee91c1e936..6287cab61f15 100644
> --- a/arch/x86/kvm/svm/svm.c
> +++ b/arch/x86/kvm/svm/svm.c
> @@ -36,6 +36,7 @@
> #include <asm/spec-ctrl.h>
> #include <asm/cpu_device_id.h>
> #include <asm/traps.h>
> +#include <asm/mshyperv.h>
>
> #include <asm/virtext.h>
> #include "trace.h"
> @@ -43,6 +44,8 @@
> #include "svm.h"
> #include "svm_ops.h"
>
> +#include "hyperv.h"
> +
> #define __ex(x) __kvm_handle_fault_on_reboot(x)
>
> MODULE_AUTHOR("Qumranet");
> @@ -928,6 +931,8 @@ static __init void svm_set_cpu_caps(void)
> kvm_cpu_cap_set(X86_FEATURE_VIRT_SSBD);
> }
>
> +static struct kvm_x86_ops svm_x86_ops;
> +
> static __init int svm_hardware_setup(void)
> {
> int cpu;
> @@ -997,6 +1002,16 @@ static __init int svm_hardware_setup(void)
> kvm_configure_mmu(npt_enabled, get_max_npt_level(), PG_LEVEL_1G);
> pr_info("kvm: Nested Paging %sabled\n", npt_enabled ? "en" : "dis");
>
> +#if IS_ENABLED(CONFIG_HYPERV)
> + if (ms_hyperv.nested_features & HV_X64_NESTED_ENLIGHTENED_TLB
> + && npt_enabled) {
> + pr_info("kvm: Hyper-V enlightened NPT TLB flush enabled\n");
> + svm_x86_ops.tlb_remote_flush = kvm_hv_remote_flush_tlb;
> + svm_x86_ops.tlb_remote_flush_with_range =
> + kvm_hv_remote_flush_tlb_with_range;
> + }
> +#endif
> +
> if (nrips) {
> if (!boot_cpu_has(X86_FEATURE_NRIPS))
> nrips = false;
> @@ -1112,6 +1127,21 @@ static void svm_check_invpcid(struct vcpu_svm *svm)
> }
> }
>
> +#if IS_ENABLED(CONFIG_HYPERV)
> +static void hv_init_vmcb(struct vmcb *vmcb)
> +{
> + struct hv_enlightenments *hve = &vmcb->hv_enlightenments;
> +
> + if (npt_enabled &&
> + ms_hyperv.nested_features & HV_X64_NESTED_ENLIGHTENED_TLB)
> + hve->hv_enlightenments_control.enlightened_npt_tlb = 1;
> +}
> +#else
> +static inline void hv_init_vmcb(struct vmcb *vmcb)
> +{
> +}
> +#endif
> +
> static void init_vmcb(struct vcpu_svm *svm)
> {
> struct vmcb_control_area *control = &svm->vmcb->control;
> @@ -1274,6 +1304,8 @@ static void init_vmcb(struct vcpu_svm *svm)
> }
> }
>
> + hv_init_vmcb(svm->vmcb);
> +
> vmcb_mark_all_dirty(svm->vmcb);
>
> enable_gif(svm);
> @@ -3967,6 +3999,9 @@ static void svm_load_mmu_pgd(struct kvm_vcpu *vcpu, unsigned long root,
> svm->vmcb->control.nested_cr3 = cr3;
> vmcb_mark_dirty(svm->vmcb, VMCB_NPT);
>
> + if (kvm_x86_ops.tlb_remote_flush)
> + kvm_update_arch_tdp_pointer(vcpu->kvm, vcpu, cr3);
> +

VMX has "#if IS_ENABLED(CONFIG_HYPERV)" around this, should we add it
here too?

> /* Loading L2's CR3 is handled by enter_svm_guest_mode. */
> if (!test_bit(VCPU_EXREG_CR3, (ulong *)&vcpu->arch.regs_avail))
> return;

--
Vitaly

2021-04-08 13:24:13

by Vineeth Pillai

[permalink] [raw]
Subject: Re: [PATCH 5/7] KVM: SVM: hyper-v: Remote TLB flush for SVM


On 4/8/21 7:18 AM, Vitaly Kuznetsov wrote:
>
>> enable_gif(svm);
>> @@ -3967,6 +3999,9 @@ static void svm_load_mmu_pgd(struct kvm_vcpu *vcpu, unsigned long root,
>> svm->vmcb->control.nested_cr3 = cr3;
>> vmcb_mark_dirty(svm->vmcb, VMCB_NPT);
>>
>> + if (kvm_x86_ops.tlb_remote_flush)
>> + kvm_update_arch_tdp_pointer(vcpu->kvm, vcpu, cr3);
>> +
> VMX has "#if IS_ENABLED(CONFIG_HYPERV)" around this, should we add it
> here too?
Agreed. Will fix.

Thanks,
Vineeth